Garcia said witnesses will play a crucial role in the investigation since the fire, which leveled four blocks of the shore’s Sandy-battered boardwalk, started in the middle of the afternoon on a nice summer day. Authorities have asked the public for any photos or videos documenting the fire’s early stages.

The blaze is thought to have started near Kohr's Frozen Custard shop, according to Seaside Park Police Chief Francis Larken. Once the fire is completely contained, investigators will pinpoint the area of origin and work from the outside perimeter of the fire inward.

Investigators will then do a physical examination in order to determine if a device or appliance may have sparked the fire – assuming foul play like arson is ruled out. “It could have been electrical wiring, the stove, compressors, anything mechanical that can overheat, anything electrical that can short out,” Garcia said.

At that point, investigators will bring in engineers and appliance experts to take apart the scene and bring evidence back to labs for examination.

“That could take a very long time,” Garcia cautioned. “Both insurance companies and appliance manufactures will be interested in the findings.”

New Jersey Gov. Chris Christie also said the investigation “will likely take days” but did not want to speculate on the cause, emphasizing that this process is standard. “There’s no import that should be drawn from the identity of the investigators or the numbers,” he said at a news briefing on Friday morning.

More than 400 firefighters responded to the scene on Thursday. The Ocean County Prosecutor’s office, along with the New Jersey State Police and The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), are currently on the ground.

Regardless of the cause, Garcia said, “It’s a tragic fire. The community definitely didn’t need this.”